How much faster (brighter) is an f0.95 lens compared to an f1.4 and f1.8? How does this affect cost?

[anthony_cicero]

1) how much more light will an f0.95 lens let in compared to an f1.4?

2) compared to an f1.8?

3) f1.4 compared to an f1.8?

 

Is the difference in (1) just more or less one stop? Difference in

(3) just ~2/3 stop?

 

If so, why is the current Nikkor 50mm prime 1.4 ~2.5x the price of

the 1.8? For less than one stop?

 

Again, this is a general question, the lenses are just for real world

example.

[walter_degroot]

this is not a direct answer,

but only the canon RF used a lens that fast.

best you can get on a film slr is f/1.2,

 

posibly there is a 1.1 somewhere.

the canon 0.95 was a BIG lens and partly obscured the viewfinder

but as I said, ask the man who owns one.

film improvements have just about negated the need for such a fast lens.

[richard_oleson]

F/0.95 is one and one-sixth stop faster than f/1.4.

 

f/0.95 is one and five-sixths stop faster than f/1.8.

 

f/1.4 is 2/3 stop faster than f/1.8.

 

I can't understand your next question. Lenses aren't priced on a flat "dollars-per-stop" rate, and your example is confusing: are you suggesting that the difference in price between an f/1.4 and an f/1.8 is less than that between an f/0.95 and an f/1.4? I may not be real up to date on pricing, but I think you'll find that one and one-sixth stop costs you a LOT more than the two-thirds stop between the 1.4 and the 1.8.....

 

The price of lenses ia mainly a function of the cost of making them. Faster lenses require more elements, more aspheric elements, and more attention to antireflection measures in addition to the fact that they use more pounds of optical glass to make. On top of that, their higher cost results in lower numbers being made, which in turn decreases economies of scale and drives the cost up further.

 

rick :)=

[ellis_vener_photography]

1.) Just over 1 stop faster f/1 > f/1.4 isa one stop difference.

 

2.) 5/3 stop.

 

3.) 2/3rds stop

 

4.) many factors; more glass, more mechanism to move the glass, many fewer are made.

Some customers are willing to pay a premium for that extra 2/3rds of a stop.

 

Leitz also made a 50mm that was an f/0.95 lens (actiully it might have been an f/0.8) .

Stankley Kubrick used it extensively in the movie "Barry Lyndon".

[andrew robertson]

I believe that Kubrick used a Zeiss when filming that movie.

[kelly_flanigan1]

the 50mm F0.7 zeiss had an adapter in front of it that made it a 36.5mm F0.7 .

[ebogaerts]

I even think that Kubrick had an adapter to make it slightly longer than 50mm's (I think 70 or 75) as well.

 

The Zeiss lens that Kubrick aquired for "Barry Lyndon" was only mountable onto the camera (I believe it was a Mitchell) after *extensive* custom modification of the movie camera's lens mount.

[jimstrutz]

Canon also made a 50mm f/1.0 for the EF mount. And, although it is not in production now, you can use it on any of the EOS film or digital SLRs as a fully automatic, autofocus lens. That extra stop cost a whole lot more than the difference between the f/1.4 and f/1.8 Canons. Also, for most purposes the f/1.4 version is a better & sharper lens than the f/1.0.

[terry_rory]

Info about that Zeiss f/0.7 lens...

 

http://www.visual-memory.co.uk/sk/ac/len/page1.htm

[dan_fromm2]

Guys, there are many, many f/0.95 lenses for cine cameras. One of the best known is the Angenieux 25/0.95.

[frank uhlig]

Ok, if I change one linear dimension of a "thingy" by a factor of 1.4 (aperture increase for 1 stop gain), then -- if everything is proportional in the bigger thingy -- i need (1.4)^3 more material. We are talking about 3D objects, like lenses, here.

 

Now get your calculator out and (1.4)^3 ~ 2.8. Any questions left to answer?

 

[if you have no calculator, just ceck the weight of the 1.4 and 1.8 lenses and see.]

 

Besides, there is a much larger market for $ 90 lenses than there is for $ 300 lenses, so economy of scale and market do play a role here, too.

[andrew robertson]

That doesn't always work, Frank. Look at Leica's 35 f/1.4 and 35 f/2 lenses - they're nearly

identical in size.

[bwcombs]

Guys, Ellis is speaking of "Stankley" Kubrick. Stanley's

photography-impaired cousin (from his second step-father's

side).

[vincenzo_maielli]

The Canon 50 mm f/ 0,95 for the Canon 7 and 7s/7sZ rangefinder is the most speed lens for civil use ever made. But the image quality at the wides apertures are very modest. A modern Leica Summilux Aspherical 50 mm f/ 1,4 or Voigtlander Cosina Nokton Aspherical 50 mm f/ 1,5 are incomparably better, in therms of sharpness, contrast, color rendition and AR treatement, than old Canon, Nikkor, Zunow and Leitz standard fast lens in the '50, '60 and '70 decades (in the range from f/ 0,95 to f/ 1,8).

Ciao.

 

 

Vincenzo Maielli Bari Italy

[anthony_cicero]

Wow, great responses.

 

I understand that the price difference in faster lenses comes from the number of elements, size of elements and proper control of light. Also, that a faster lens needs to open up much wider makes complete sense...not surprising that the f.95 Canon blocks part of the viewfinder.

 

Some part of me thinks it's strange that as you approach f0 (if there is such a thing), it seems you'll hit a theoretical limit to how wide an aperture can be used.

 

It bugs me that a lens is at its worst wide open. I rarely even find I can get close to f16, I'm always groping for more light. I guess I should take that up with mother nature. Maybe I need to shoot in bright sunlight more often.

 

Thanks to everyone for the responses.

[dan_fromm2]

The theoretical limit in air is f/0.5. Oil immersion microscope objectives attain ~ f/0.35.

[anthony_cicero]

Dan, what is the limiting factor?

[dan_fromm2]

http://www.microscopyu.com/articles/formulas/formulasna.html